Railroad gondola cars are widely used to transport a variety of cargos. Several techniques are known for loading and unloading the cargos.
Gondola cars may be loaded and unloading by hoists, cranes or conveyors which are stationarily mounted with respect to railroad tracks on which the gondola cars run. This arrangement requires that each gondola car be sequentially positioned sufficiently close to the stationary loader to permit the loader to reach the car. Where a coupled line of gondola cars is to be loaded or unloaded, the line of cars may have to be moved each time one or a few cars have been unloaded in order that the loader may reach additional cars. This requires that a traction engine be periodically operated throughout the loading or unloading of a line of cars.
Accordingly, it is an object of the present invention to provide a gondola car loader which is moveable with respect to a stationary line of gondola cars.
Gondola cars may be loaded and unloaded by mobile loaders which travel along the ground adjacent to a line of gondola cars. This loading technique has a disadvantage in that the mobile loader must be provided with a right of way paralleling railroad tracks on which gondola cars run.
It is another object of the present invention to provide a gondola car loader, moveable with respect to stationary gondola cars, which does not require a right of way adjacent to the railroad track on which the gondola cars are run.
A known method of loading ore cars, illustrated in U.S. Pat. No. 2,906,212 to Hayes, employs specially designed ore cars providing a runway on their top faces on which a loader vehicle may be driven. The loader vehicle is equipped with track laying wheels.
The loader is not, however, adapted for use on conventional gondola cars since the tops of conventional gondola cars do not form nearly continuous runways when the cars are adjacent one another on a railroad track.
Accordingly, it is yet another object of the present invention to provide a loader for conventional gondola cars which is moveable across the tops of adjacent gondola cars without modification of the cars to provide a nearly continuous runway across the tops of the cars.
An apparatus moveable along the top edges of adjacent gondola cars is shown in a later filed U.S. Patent Application (Ser. No. 789,887, filed Apr. 22, 1977) which application is assigned to the same assignee as the subject application.
These and other objects of the invention will become apparent from the claims and from the following description when read in conjunction with the appended drawings.